Promoting Global Internet Freedom:
Policy and Technology
Patricia Moloney Figliola
Specialist in Internet and Telecommunications Policy
April 23, 2013
Congressional Research Service
7-5700
www.crs.gov
R41837
CRS Report for Congress
Pr
epared for Members and Committees of Congress
Promoting Global Internet Freedom: Policy and Technology
Summary
Modern communication tools such as the Internet provide a relatively inexpensive, accessible,
easy-entry means of sharing ideas, information, and pictures around the world. In a political and
human rights context, in closed societies when the more established, formal news media is denied
access to or does not report on specified news events, the Internet has become an alternative
source of media, and sometimes a means to organize politically.
The openness and the freedom of expression allowed through social networking sites, as well as
the blogs, video sharing sites, and other tools of today’s communications technology, have proven
to be an unprecedented and often disruptive force in some closed societies. Governments that
seek to maintain their authority and control the ideas and information their citizens receive are
often caught in a dilemma: they feel that they need access to the Internet to participate in
commerce in the global market and for economic growth and technological development, but fear
that allowing open access to the Internet potentially weakens their control over their citizens.
Internet freedom can be promoted in two ways, through legislation that mandates or prohibits
certain activities, or through industry self-regulation. Current legislation under consideration by
Congress, the Global Online Freedom Act of 2011 (H.R. 3605), would prohibit or require
reporting of the sale of Internet technologies and provision of Internet services to “Internet-
restricting countries” (as determined by the State Department). Some believe, however, that
technology can offer a complementary and, in some cases, better and more easily implemented
solution to ensuring Internet freedom. They argue that hardware and Internet services, in and of
themselves, are neutral elements of the Internet; it is how they are implemented by various
countries that is repressive. Also, Internet services are often tailored for deployment to specific
countries; however, such tailoring is done to bring the company in line with the laws of that
country, not with the intention of allowing the country to repress and censor its citizenry. In many
cases, that tailoring would not raise many questions about free speech and political repression.
This report provides information about federal and private sector efforts to promote and support
global Internet freedom and a description of Internet freedom legislation and hearings from the
112th Congress. Three appendixes suggest further reading on this topic and describe censorship
and circumvention technologies.
Congressional Research Service
Promoting Global Internet Freedom: Policy and Technology
Contents
Introduction ...................................................................................................................................... 1
Doing Business with Repressive Regimes: U.S. Industry Dilemma ............................................... 1
U.S. Government Activity Promoting Internet Freedom ................................................................. 2
Department of State ................................................................................................................... 2
The NetFreedom Task Force ............................................................................................... 3
The State Department’s International Strategy for Cyberspace .......................................... 4
Broadcasting Board of Governors ............................................................................................. 5
U.S. Industry Activity Promoting Internet Freedom: The Global Network Initiative ..................... 5
GNI Report: Protecting Human Rights in the Digital Age ........................................................ 6
Legislative Activity in the 113th Congress ....................................................................................... 7
Legislative Activity in the 112th Congress ....................................................................................... 7
Legislation ................................................................................................................................. 8
Hearings ..................................................................................................................................... 8
Appendixes
Appendix A. For Further Reading ................................................................................................... 9
Appendix B. Methods/Technologies Used to Monitor and Censor Websites and Web-
Based Communications .............................................................................................................. 10
Appendix C. Technologies Used to Circumvent Censorship ......................................................... 12
Contacts
Author Contact Information........................................................................................................... 13
Acknowledgments ......................................................................................................................... 13
Congressional Research Service
Promoting Global Internet Freedom: Policy and Technology
Introduction
Around the world, over 2 billion people have access to the Internet. Most use this access to
conduct activities related to their day-to-day lives—such as accessing government services,
banking and paying bills, communicating with friends and relatives, researching health
information, and, in some cases, participating in their counties’ political processes. In most
countries, those who use the Internet to participate in their countries’ political processes take for
granted that they may use the Internet to engage openly in political discussions and to organize
politically-oriented activities.
However, the freedoms of speech, association, and assembly—including both political speech and
organizing conducted via the Internet—are not available to citizens in every country. In some
countries activists are in danger any time they access or even attempt to access a prohibited
website or service or promote political dissent. Political activity is monitored and tracked. Despite
such hurdles, political activists have embraced the Internet, using it to share information and
organize dissent. To protect themselves, they have purchased and deployed circumvention
technologies to skirt government censors.
The restriction of Internet freedom by foreign governments creates a tension between U.S.
policymakers and industry. One of the most fundamental of these tensions is between the
commercial needs of U.S. industry, which faces competitive and legal pressures in international
markets, and the political interests of the United States, which faces other pressures (e.g., national
security, global politics). This tension is complicated by the fact that many of the technologies in
question may be used both for and against Internet freedom, in some cases simultaneously.
This report provides information about federal and private sector efforts to promote and support
global Internet freedom, a description of Internet freedom legislation from the 112th Congress,
and suggestions for further reading on this topic. Two appendixes describe censorship and
circumvention technologies.
Doing Business with Repressive Regimes:
U.S. Industry Dilemma
Governments everywhere need the Internet for economic growth and technological development.
Some also seek to restrict the Internet in order to maintain social, political, or economic control.
Such regimes often require the assistance of foreign Internet companies operating in their
countries. These global technology companies find themselves in a dilemma. They must either
follow the laws and requests of the host country, or refuse to do so and risk the loss of business
licenses or the ability to sell services in that country.
However, the global technology industry also risks raising the concern of U.S. lawmakers by
appearing to be complicit with a repressive regime if they cooperate. For example, the Global
Online Freedom Act of 2011 (GOFA) (H.R. 3605), introduced by Representative Christopher
Smith, would prohibit or require reporting of the sale of Internet technologies and provision of
Internet services to “Internet-restricting countries” (as determined by the State Department). That
legislation mirrors opinions of some who believe that the U.S. technology industry should be
doing more to ensure that its products are not used for repressive purposes.
Congressional Research Service
1
Promoting Global Internet Freedom: Policy and Technology
Others believe that technology can offer a complementary (and, in some cases, better) solution to
prevent government censorship than mandates imposed on companies. Hardware, software, and
Internet services, in and of themselves, are neutral elements of the Internet; it is how they are
implemented by various countries that makes them “repressive.” For example, software is needed
by Internet service providers (ISPs) to provide that service. However, software features intended
for day-to-day Internet traffic management, such as filtering programs that catch spam or viruses,
can be misused. Repressive governments use such programs to censor and monitor Internet
traffic—sometimes using them to identify specific individuals for persecution. Further, U.S.
technology representatives note that it is not currently feasible to completely remove these
programs, even when sold to countries that use those features to repress political speech, without
risking significant network disruptions.1
On the other hand, widely used Internet services, such as search engines, are often tailored for
specific countries. Such tailoring is done to bring the company’s products and services in line
with the laws of that country, and not with the end goal of allowing the country to repress and
censor its citizenry. In many cases, tailoring does not raise many questions about free speech and
political repression because the country is not considered to be a repressive regime. Under
Canadian human rights law, for example, it is illegal to promote violence against protected
groups; therefore, when reported, Google.ca will remove such links from search results.2
U.S. Government Activity Promoting
Internet Freedom
Both the Department of State and the Broadcasting Board of Governors (BBG) have an active
role in fighting Internet censorship.
Department of State
The State Department works to “protect and defend a free and open Internet”3 as an element of its
policy supporting universal rights of freedom of expression and the free flow of information. It
supports the following key initiatives to advance Internet freedom as an objective of U.S. foreign
policy:4
• Continue the work of the State Department’s NetFreedom Task Force (previously
called the Global Internet Freedom Task Force (GIFT)). The Task Force oversees
U.S. efforts in more than 40 countries to help individuals circumvent politically
motivated censorship by developing new tools and providing the training needed
to safely access the Internet;
1 Testimony of Mark Chandler, Cisco Systems, before the Senate Committee on the Judiciary Subcommittee on Human
Rights and the Law, May 2, 2008.
2 Testimony of Nicole Wong, Google, before the Senate Committee on the Judiciary Subcommittee on Human Rights
and the Law, May 2, 2008.
3 Secretary of State Hillary Rodham Clinton, “Internet Rights and Wrongs: Choices & Challenges in a Networked
World,” February 15, 2011, http://www.state.gov/secretary/rm/2011/02/156619.htm.
4 Hillary Rodham Clinton, “Remarks on Internet Freedom,” January 21, 2010, http://www.state.gov/secretary/rm/2010/
01/135519.htm.
Congressional Research Service
2
Promoting Global Internet Freedom: Policy and Technology
• Make Internet freedom an issue at the United Nations and the U.N. Human
Rights Council in order to enlist world opinion and support for Internet Freedom;
• Work with new partners in industry, academia, and non-governmental
organizations to establish a standing effort to advance the power of “connection
technologies” that will empower citizens and leverage U.S. traditional
diplomacy;
• Provide new, competitive grants for ideas and applications that help break down
communications barriers, overcome illiteracy, and connect people to servers and
information they need;
• Urge and work with U.S. media companies to take a proactive role in challenging
foreign governments’ demands for censorship and surveillance; and
• Encourage the voluntary work of the communications-oriented, private sector-led
Global Network Initiative (GNI). The GNI brings technology companies,
nongovernmental organizations, academic experts, and social investment funds
together to develop responses and mechanisms to government requests for
censorship.
Commentators have expressed concerns that there could be serious negative consequences for
U.S. and foreign companies, and U.S. or foreign nationals working or living in countries with
repressive regimes, if they follow the expanded U.S. policy supporting Internet freedom. These
commentators point out that repressive governments could punish or make an example of an
individual or company for not following the dictates of that country. This could include
harassment, lifting of business licenses, confiscation of assets, or imprisonment. Observers also
question what powers the United States may have to respond to such actions, beyond expressing
displeasure through official demarches and public statements or through negotiations.5
The NetFreedom Task Force
The Task Force is the State Department’s policy-coordinating and outreach body for Internet
freedom. The members address Internet freedom issues by drawing on the Department’s
multidisciplinary expertise in international communications policy, human rights,
democratization, business advocacy, corporate social responsibility, and relevant countries and
regions. The Task Force is co-chaired by the Under Secretaries of State for Democracy and
Global Affairs and for Economic, Business, and Agricultural Affairs and draws on the State
Department’s multidisciplinary expertise in its regional and functional bureaus to work on issues
such as international communications, human rights, democratization, business advocacy and
corporate social responsibility, and country specific concerns. The Task Force supports Internet
freedom by6
5 Questions following Secretary of State Hillary Clinton’s Remarks on Internet Freedom, January 21, 2010,
http://www.state.gov/secretary/rm/2010/01/135519.htm, and questions following Assistant Secretary of State Michael
Posner’s “Briefing on Internet Freedom and 21st Century Statecraft,” January 22, 2010, http://it.tmcnet.com/news/2010/
01/26/4590599.htm.
6 The GIFT Strategy is available online at http://2001-2009.state.gov/g/drl/rls/78340.htm.
Congressional Research Service
3
Promoting Global Internet Freedom: Policy and Technology
• monitoring Internet freedom and reporting in its annual Country Reports on
Human Rights Practices the quality of Internet freedom in each country around
the world;
• responding in both bilateral and international fora to support Internet freedom;
and
• expanding access to the Internet with greater technical and financial support for
increasing availability of the Internet in the developing world.
The State Department’s International Strategy for Cyberspace
In May 2011, the State Department released, “International Strategy for Cyberspace: Prosperity,
Security, and Openness in a Networked World.”7 This report contains a section called “Internet
Freedom: Fundamental Freedoms and Privacy,” which sets out a four-pronged strategy to help
secure fundamental freedoms and privacy in cyberspace.
Support civil society actors in achieving reliable, secure, and safe platforms for freedoms of
expression and association
The State Department supports individual use of digital media to express opinions, share
information, monitor elections, expose corruption, and organize social and political movements,
and denounce those who harass, unfairly arrest, threaten, or commit violent acts against the
people who use these technologies. The department believes that the same protections must apply
to ISPs and other providers of connectivity, “who too often fall victim to legal regimes of
intermediary liability that pass the role of censoring legitimate speech down to companies.”
Collaborate with civil society and nongovernment organizations to establish safeguards
protecting their Internet activity from unlawful digital intrusions
The State Department will promote cybersecurity among civil society and nongovernmental
organizations to help ensure that freedoms of speech and association are more widely enjoyed in
the digital age.
Cybersecurity is particularly important for activists, advocates, and journalists on the front
lines who may express unpopular ideas and opinions, and who are frequently the victims of
disruptions and intrusions into their email accounts, websites, mobile phones, and data
systems. The United States supports efforts to empower these users to protect themselves, to
help ensure their ability to exercise their free expression and association rights on the new
technologies of the 21st century.
Encourage international cooperation for effective commercial data privacy protections
The State Department believes that protecting individual privacy is essential to maintaining the
trust that sustains economic and social uses of the Internet.
The United States has a robust record of enforcement of its privacy laws, as well as
encouraging multi-stakeholder policy development We are continuing to strengthen the U.S.
7 U.S. State Department, “International Strategy for Cyberspace, Prosperity, Security, and Openness in a Networked
World,” http://www.whitehouse.gov/sites/default/files/rss_viewer/international_strategy_for_cyberspace.pdf.
Congressional Research Service
4
Promoting Global Internet Freedom: Policy and Technology
commercial data privacy framework to keep pace with the rapid changes presented by
networked technologies We recognize the role of applying general privacy principles in the
commercial context while maintaining the flexibility necessary for innovation. The United
States will work toward building mutual recognition of laws that achieve the same objectives
and enforcement cooperation to protect privacy and promote innovation.
Ensure the end-to-end interoperability of an Internet accessible to all
The final prong of the strategy is that users should have confidence that the information they send
over the Internet will be received as it was intended, anywhere in the world, and that under
normal circumstances, data will flow across borders without regard for its national origin or
destination.
Ensuring the integrity of information as it flows over the Internet gives users confidence in
the network and keeps the Internet open as a reliable platform for innovation that drives
growth in the global economy and encourages the exchange of ideas among people around
the world. The United States will continue to make clear the benefits of an Internet that is
global in nature, while opposing efforts to splinter this network into national intranets that
deprive individuals of content from abroad.
Broadcasting Board of Governors
The BBG directly funds some of the initiatives to develop software and other technologies that
allow dissidents to circumvent censorship and surveillance by their governments, and
communicate freely. Through the BBG, the U.S. government spends about $30 million a year to
develop circumvention tools in support of Internet freedom.
The popularity and success of these initiatives, however, have become a liability as the number of
users grows at increasingly rapid rates. The tools are being overwhelmed by demand and there is
not enough money available to expand capacity. The result is online bottlenecks that have made
the tools slow and often inaccessible to users in China, Iran, and elsewhere.
U.S. Industry Activity Promoting Internet Freedom:
The Global Network Initiative8
In response to criticism, particularly of their operations in China, a group of U.S. information and
communications technology companies, along with civil society organizations, investors, and
academic entities, formed the Global Network Initiative (GNI) in 2008. The GNI aims to promote
best practices related to the conduct of U.S. companies in countries with poor Internet freedom
records.9 The GNI adopts a self-regulatory approach to promote due diligence and awareness
regarding human rights. A set of principles and supporting mechanisms provides guidance to the
ICT industry and its stakeholders on how to protect and advance freedom of expression and the
8 The GNI 2012 Annual Report is online at http://globalnetworkinitiative.org/sites/default/files/
GNI%20Annual%20Report%202012.pdf.
9 The GNI website is online at http://www.globalnetworkinitiative.org/index.php. The 2011 GNI annual report is
available online at http://www.globalnetworkinitiative.org/files/GNI_2011_Annual_Report.pdf.
Congressional Research Service
5
Promoting Global Internet Freedom: Policy and Technology
right to privacy when faced with pressures from governments to take actions that infringe upon
these rights.10 Companies undergo third-party assessments of their compliance with GNI
principles. Although some human rights groups have criticized the GNI’s guidelines for being
weak or too broad, the GNI’s supporters argue that the initiative sets realistic goals and creates
real incentives for companies to uphold free expression and privacy.11
GNI Report: Protecting Human Rights in the Digital Age
In February 2011, the GNI released the report, “Protecting Human Rights in the Digital Age.”12 In
the report, the authors explain the importance of understanding the ICT industry’s “freedom of
expression and privacy risk drivers” and characteristics that distinguish it from other industry
sectors. The report goes on to explain the characteristics that exist across five spheres and have
implications for how to best protect and advance human rights in the industry:
• End user—plays a significant role in the human rights impact of ICT
• Legal frameworks—can move more slowly than ICT product and service
development
• Jurisdictional complexity—increasingly significant as information becomes
global and data flows across borders
• Technological complexity—new products and services are continually
introduced, often with unpredictable consequences for human rights
• B2B relationships with enterprise and government customers—with whom ICT
companies often co-design products and services.
The GNI provides direction and guidance to companies on how to respond to government
demands to remove, filter, or block content, and how to respond to law enforcement agency
demands to disclose personal information. These types of risk drivers will be relevant for
companies that hold significant amounts of personal information and/or act as gatekeepers to
content, primarily telecommunications services providers and internet services companies.
The report sets out the following “risk drivers” across eight segments of the ICT industry:
• Telecommunications Services—risk drivers include requirements to assist law
enforcement agencies in investigations
• Cell Phones and Mobile Devices—location-based services such as mapping or
advertising can present new sources of security and privacy risks
• Internet Services—companies can receive demands to remove, block, or filter
content, or deactivate individual user accounts
10 http://www.globalnetworkinitiative.org/index.php
11 Elisa Massimino, Human Rights First, “Judge the Global Network Initiative by How It Judges Companies,” March
31, 2011; Douglass MacMillan, “Google, Yahoo Criticized over Foreign Censorship,” BusinessWeek, March 13, 2009.
12 Global Network Initiative, “Protecting Human Rights in the Digital Age,” February 2011,
http://www.globalnetworkinitiative.org/cms/uploads/1/BSR_ICT_Human_Rights_Report.pdf
Congressional Research Service
6
Promoting Global Internet Freedom: Policy and Technology
• Enterprise Software, Data Storage, and IT Services—companies hosting data “in
the cloud” may increasingly be gatekeepers to law enforcement requests or
provide service to high-risk customers
• Semiconductors and Chips—hardware can be configured to allow remote access,
which may present security and privacy risks
• Network Equipment—where functionality necessarily allows content to be
restricted or data to be collected by network managers
• Consumer Electronics—pressure may exist to pre-install certain types of
software to restrict access to content or allow for surveillance
• Security Software—risk drivers may include increasing pressure to offer simpler
means of unscrambling encrypted information.
The GNI report concludes by highlighting four key topics that any ongoing dialogue about the
technology industry should likely address: relationships with governments; designing future
networks; implementing due diligence; and engaging employees, users, and consultants.
Legislative Activity in the 113th Congress
Representative Christopher Smith introduced the Global Online Freedom Act of 2013, H.R. 491,
on February 4, 2013. The bill was referred to House Subcommittee on Africa, Global Health,
Global Human Rights, and International Organizations. Among other goals, H.R. 491would:
• Make it U.S. policy to deter U.S. businesses from cooperating with Internet-
restricting countries in effecting online censorship.
• Amend the Foreign Assistance Act of 1961 to require assessments of electronic
information freedom in each foreign country.
• Direct the Secretary of State to annually designate Internet-restricting countries.
• Amend the Securities Exchange Act of 1934 to require each Internet
communications services company that operates in an Internet-restricting country
to include in its annual report information relating to human rights due diligence,
policies pertaining to the collection of personally identifiable information, and
restrictions on Internet search engines or content hosting services.
• Amend the Export Administration Act of 1979 to direct the Secretary of
Commerce to establish a list of technologies (and related goods) that would assist
censorship or surveillance efforts by a foreign government and prohibit export of
those items to a government in any Internet-restricting country.
Legislative Activity in the 112th Congress
In the 112th Congress, there was one piece of legislation introduced and two hearings held.
Congressional Research Service
7
Promoting Global Internet Freedom: Policy and Technology
Legislation
Representative Christopher Smith introduced the Global Online Freedom Act of 2011, H.R. 3605,
on December 12, 2011. The bill was ordered to be reported, as amended, on March 27, 2012.
H.R. 3605 was substantially the same as H.R. 491 that has been introduced in the 113th Congress.
Hearings
Two hearings were also been held on the subject of Global Internet Freedom.
• Congressional-Executive Commission on China, China’s Censorship of the
Internet and Social Media: The Human Toll and Trade Impact, November 17,
2011.
• House Committee on Foreign Affairs, Subcommittee on Africa, Global Health,
and Human Rights, Promoting Global Internet Freedom, December 8, 2011.
Congressional Research Service
8
Promoting Global Internet Freedom: Policy and Technology
Appendix A. For Further Reading
“Leaping over the Firewall: A Review of Censorship Circumvention Tools,”
Freedom House
April 2011
http://www.freedomhouse.org/template.cfm?page=383&report=97
Report
“Freedom on the Net 2011: A Global Assessment of Internet and Digital Media”
Freedom House
September 2012
http://www.freedomhouse.org/uploads/fotn/2011/FOTN2011.pdf
Report
(Main report page: http://www.freedomhouse.org/report/freedom-net/freedom-net-2012)
“Protecting Human Rights in the Digital Age”
Global Network Initiative
February 2011
http://www.globalnetworkinitiative.org/cms/uploads/1/BSR_ICT_Human_Rights_Report.pdf
Report
“The Political Power of Social Media: Technology, the Public Sphere, and Political Change”
Foreign Affairs (Journal of the Council on Foreign Relations), by Clay Shirky
January/February 2011
http://www.foreignaffairs.com/articles/67038/clay-shirky/the-political-power-of-social-media
*Full article not available online.
Article
Congressional Research Service
9
Promoting Global Internet Freedom: Policy and Technology
Appendix B. Methods/Technologies Used to
Monitor and Censor Websites and Web-Based
Communications13
There are four different types of targets that are censored:
• Services, e.g., email, the web, peer-to-peer, social networking service
• Content, e.g., hate speech, child pornography, gambling, human-rights
organizations, independent news sites, political opposition sites
• Activities, e.g., illegal music downloads, spam, political organizing by opposition
groups in repressive regimes.
These targets can be censored using the methods listed below.
Key-Word List Blocking
This is a simple type of filtration where a government drops any Internet packets featuring certain
keywords, such as “protest” or “proxy.”
Domain Name System (DNS) Poisoning
DNS poisoning intentionally introduces errors into the Internet’s directory service to misdirect the
original request to another IP address.
IP Blocking
IP Blocking is one of the most basic methods that governments use for censorship, as it simply
prevents all packets going to or from targeted IP addresses. This is an easy technology to
implement, but it does not address the problem of individual communications between users. This
method is used to block banned websites, including news sites and proxy servers that would allow
access to banned content, from being viewed.
Bandwidth Throttling
Bandwidth throttling simply limits the amount of traffic that can be sent over the Internet.
Keeping data volume low facilitates other methods of monitoring and filtering by limiting the
amount of data present.
13 Adapted from “Leaping Over the Firewall: A Review of Censorship Circumvention Tools,” Freedom House, April
2011, http://www.freedomhouse.org/template.cfm?page=383&report=97 ;“The State of Iranian Communication:
Manipulation and Circumvention,” Morgan Sennhauser, Nedanet, July 2009, http://iranarchive.openmsl.net/SoIC-
1.21.pdf; and “Five Technologies Iran is Using to Censor the Web,” Brad Reed, Network World, July 2009,
http://www.networkworld.com/news/2009/072009-iran-censorship-tools.html.
Congressional Research Service
10
Promoting Global Internet Freedom: Policy and Technology
Traffic Classification
This is a much more sophisticated method of blocking traffic than IP blocking, as governments
can halt any file sent through a certain type of protocol, such as FTP. Because FTP transfers are
most often sent through a specific communications port, a government can simply limit the
bandwidth available on that port and throttle transfers. This type of traffic-shaping practice is the
most common one used by repressive governments today. It is not resource intensive and it is
fairly easy to implement.
Shallow Packet Inspection (SPI)
Shallow packet inspection is a less sophisticated version of the deep packet inspection (DPI)
technique (DPI is described below) that is used to block packets based on their content. Unlike
DPI, which intercepts packets and inspects their fingerprints (fingerprinting is described below),
headers, and payloads, SPI makes broad generalities about traffic based solely on evaluating the
packet header. Although shallow packet inspection can’t provide the same refined/detailed traffic
assessments as DPI, it is much better at handling volume than DPI.
SPI is much less refined than DPI, but it is capable of handling a greater volume of traffic much
more quickly. SPI is akin to judging a book by its cover. This method is prone to exploitation by
users because they can disguise their packets to look like a different kind of traffic.
Packet Fingerprinting
This is a slightly more refined method of throttling packets than shallow packet inspection, as it
looks not only at the packet header but at its length, frequency of transmission, and other
characteristics to make a rough determination of its content. In this manner, the government can
better classify packets and not throttle traffic sent out by key businesses.
Deep Packet Inspection (DPI) / Packet Content Filtering
DPI is the most refined method that governments have for blocking Internet traffic. As mentioned
above, deep packet inspectors examine not only a packet’s header but also its payload. For
instance, certain keywords can be both monitored and the e-mail containing them can be kept
from reaching its intended destination.
This gives governments the ability to filter packets at a more surgical level than any of the other
techniques discussed so far. While providing the most targeted traffic monitoring and shaping
capabilities, DPI is also more complicated to run and is far more labor-intensive than other
traffic-shaping technologies.
Congressional Research Service
11
Promoting Global Internet Freedom: Policy and Technology
Appendix C. Technologies Used to
Circumvent Censorship14
Each of the circumvention methods explained below can, in general, be considered an anonymous
“proxy server.” A proxy server is a computer system or an application program that acts as an
intermediary for requests from a user seeking resources from other servers, allowing the user to
block access to his or her identity and become anonymous.
Web-Based Circumvention Systems
Web-based circumvention systems are special web pages that allow users to submit a URL and
have the web-based circumventor retrieve the requested web page. There is no connection
between the user and the requested website as the circumventor transparently proxies the request
allowing the user to browse blocked websites seamlessly. Since the web addresses of public
circumventors are widely known, most Internet filtering applications already have these services
on their block lists, as do many countries that filter at the national level.
Examples: Proxify, StupidCensorhip, CGIProxy, psiphon, Peacefire/Circumventor.
Web and Application Tunneling Software
Tunneling encapsulates one form of traffic inside of other forms of traffic. Typically, insecure,
unencrypted traffic is tunneled within an encrypted connection. The normal services on the user’s
computer are available, but run through the tunnel to the non-filtered computer which forwards
the user’s requests and their responses transparently. Users with contacts in a non-filtered country
can set up private tunneling services while those without contacts can purchase commercial
tunneling services. “Web” tunneling software restricts the tunneling to web traffic so that web
browsers will function securely, but not other applications. “Application” tunneling software
allows the user to tunnel multiple Internet applications, such as e-mail and instant messenger
applications.
Examples: Web Tunneling: UltraReach, FreeGate, Anonymizer, Ghost Surf.
Examples: Application Tunneling: GPass, HTTP Tunnel, Relakks, Guardster/SSH.
Anonymous Communications Systems
Anonymous technologies conceal a user’s IP address from the server hosting the website visited
by the user. Some, but not all, anonymous technologies conceal the user’s IP address from the
anonymizing service itself and encrypt the traffic between the user and the service. Since users of
anonymous technologies make requests for web content through a proxy service, instead of to the
server hosting the content directly, anonymous technologies can be a useful way to bypass
14 Adapted from Reporters Without Borders, “Handbook for Bloggers and Cyber-Dissidents,” September 2005,
http://www.rsf.org/IMG/pdf/Bloggers_Handbook2.pdf; and The Citizen Lab, “Everyone’s Guide to By-Passing Internet
Censorship for Citizens Worldwide,” University of Toronto, September 2007, http://citizenlab.org/Circ_guide.pdf.
Congressional Research Service
12
Promoting Global Internet Freedom: Policy and Technology
Internet censorship. However, some anonymous technologies require users to download software
and can be easily blocked by authorities.
Examples: Tor, JAP ANON, I2P
Author Contact Information
Patricia Moloney Figliola
Specialist in Internet and Telecommunications
Policy
pfigliola@crs.loc.gov, 7-2508
Acknowledgments
Casy Addis, Thomas Lum, Kennon H. Nakamura, and Gina Stevens contributed to a previous
version of this report.
Congressional Research Service
13